Y12W08VC Thinking in expected value

In 2004, a professional poker player made an excellent decision and lost the tournament. Most people would say she made a bad decision — she lost. Good decisions produce good outcomes, don't they? The player, Annie Duke, would later argue this logic is fundamentally wrong. This week's article examines a specific way of thinking about decisions — expected value — that separates the quality of a choice from the quality of its outcome.

Core Vocabulary

deliberation

/dɪˌlɪbəˈreɪʃən/|de·lib·er·a·tion

n

Careful consideration or discussion of options before making a decision.

Word Breakdown: de- (away from, Latin) + liber- (weigh/balance) + -ation (the act of)

Word family: deliberate (v./adj.), deliberately (adv.), deliberation (n.)

Synonyms: consideration, thought, reflection

Collocations: careful deliberation, deliberation on options, after deliberation

Example: The moment you introduce probability into your reasoning, the picture changes completely.

In the articleMost people hearing that story would say she made a bad decision.

resulting

/rɪˈzʌltɪŋ/|re·sult·ing

adj

Duke's term for the cognitive error of judging decision quality by its outcome rather than by the quality of reasoning.

Word family: result (v./n.), resulting (v./adj.), resultant (adj.)

Synonyms: outcome-bias, result-focused

Collocations: resulting bias, resulting in, avoid resulting

Example: The core insight — Duke calls it resulting — is that good decisions don't always produce good outcomes.

In the articleThe core insight — Duke calls it resulting — is that good decisions don't always produce good outcomes, and bad decisions don't always produce bad ones.

probability

/ˌprɒbəˈbɪləti/|prob·a·bil·i·ty

n

The likelihood or chance that something will occur, expressed as a numerical value between 0 and 1.

Word Breakdown: prob- (to test, Latin) + -ability (quality or state of)

Word family: probability (n.), probable (adj.), probably (adv.)

Synonyms: likelihood, chance, odds

Collocations: high probability, probability of success, calculate probability

Example: Judging by outcomes alone would tell you all three had done well. The moment you introduce probability into your reasoning, the picture changes completely.

In the articleJudging by outcomes alone would tell you all three had done well. The moment you introduce probability into your reasoning, the picture changes completely.

variance

/ˈveərɪəns/|var·i·ance

n

The spread or range of possible outcomes from a decision or event; the degree to which outcomes vary.

Word Breakdown: var- (change, Latin) + -ance (the state of)

Word family: variance (n.), vary (v.), variable (n./adj.), varying (adj.)

Synonyms: variation, dispersion, range

Collocations: variance in outcomes, high variance, low variance

Example: Most meaningful decisions involve uncertainty, which means their outcomes are, in statistical terms, samples from a distribution.

In the articleMost meaningful decisions involve uncertainty, which means their outcomes are, in statistical terms, samples from a distribution.

calibrate

/ˈkælɪbreɪt/|cal·i·brate

vb | [calibrates, calibrated, calibrating]

To adjust or refine something to achieve accuracy; to align predictions with reality.

Word Breakdown: cal- (to measure, Latin) + -ibrate (to adjust/regulate)

Word family: calibrate (v.), calibrating (v.), calibrated (adj.), calibration (n.)

Synonyms: adjust, tune, fine-tune

Collocations: calibrate predictions, calibrate estimates, calibrate probability

Example: The superforecasters calibrated their probability estimates by updating them as new information arrived.

In the articleTetlock wanted to know whether some people were genuinely better than others at predicting world events — and whether that skill could be learned.

consequential

/ˌkɒnsɪˈkwenʃəl/|con·se·quen·tial

adj

Having significant effects or importance; producing meaningful results or consequences.

Word Breakdown: con- (together, Latin) + sequ- (follow) + -ential (relating to)

Word family: consequence (n.), consequential (adj.), consequently (adv.)

Synonyms: significant, important, substantial

Collocations: consequential decision, consequential impact, consequential choice

Example: Most people's lives contain many decisions you'll make many times and can recover from, and a small number of consequential decisions where a single bad outcome could end the game.

In the articleMost meaningful decisions involve uncertainty, which means their outcomes are, in statistical terms, samples from a distribution.

systematic

/ˌsɪstəˈmætɪk/|sys·tem·at·ic

adj

Following or organized according to a regular method or system; methodical and organized.

Word Breakdown: sys- (together, Greek) + tem- (arrange) + -atic (relating to)

Word family: system (n.), systematic (adj.), systematically (adv.)

Synonyms: methodical, organized, planned

Collocations: systematic approach, systematic error, systematic thinking

Example: Expected-value reasoning requires a systematic approach to thinking about probabilities rather than intuitive judgment.

In the articleA separate body of research, led by Jonathan Baron and John Hershey in the 1980s, documented what they called outcome bias: when participants were shown identical decisions that had produced different outcomes (by random chance), they consistently rated the decision that had produced the better outcome as higher quality — even though the decision itself was the same.

asymmetric

/ˌeɪsɪˈmetrɪk/|a·sym·met·ric

adj

Not balanced or equal on both sides; unequal in magnitude or distribution.

Word Breakdown: a- (not) + symmetric (balanced)

Word family: asymmetry (n.), asymmetric (adj.), asymmetrically (adv.)

Synonyms: unequal, unbalanced, one-sided

Collocations: asymmetric payoff, asymmetric information, asymmetric risk

Example: An asymmetric payoff situation is where upside and downside are unequal in magnitude.

In the articleBut for a small number of decisions — the ones where a single bad outcome could end the game — expected-value thinking needs to be overridden by survival thinking.

Technical Terms

expected value

/ɪkˈspektɪd ˈvæljuː/|ex·pect·ed val·ue

noun phrase

The probability-weighted average of all possible outcomes of a decision; the sum of (probability × payoff) across all scenarios.

Synonyms: weighted average outcome, probability-weighted value, expected payoff

Collocations: calculate expected value, positive expected value, expected value calculation

Example: When you calculate the expected value of a business investment at 0.6 probability of gaining $10,000 and 0.4 probability of losing $3,000, you get (0.6 × 10,000) + (0.4 × -3,000) = $4,800.

In the articleIn other words, poker is a game of expected value: make positive-expected-value decisions long enough, and the mathematics will reward you.

decision quality

/dɪˈsɪʒən ˈkwɒlɪti/|de·ci·sion qual·i·ty

noun phrase

Annie Duke's concept distinguishing how well a decision was reasoned from how well it turned out; a measure of process, not outcome.

Synonyms: reasoning quality, process quality, decision excellence

Collocations: assess decision quality, decision quality vs. outcome quality, improve decision quality

Example: A doctor makes a high-quality decision by correctly diagnosing a rare disease based on available evidence, even if the patient's outcome is poor due to advanced complications.

In the articleShe calls this move 'resulting' — and argues it is the enemy of decision quality.

resulting

/rɪˈzʌltɪŋ/|re·sult·ing

noun (Duke's coinage)

Annie Duke's term for the systematic error of judging the quality of a decision by its outcome rather than by the reasoning behind it.

Synonyms: outcome bias, result-focused judgment, hindsight bias

Collocations: avoid resulting, the resulting trap, practice resulting

Example: A CEO makes a bold strategic move with sound reasoning, but when the market shifts unexpectedly, resulting causes the board to judge the decision as poor, even though the reasoning was sound.

In the articleShe calls this move 'resulting' — and argues it is the enemy of decision quality.

variance

/ˈveəriəns/|var·i·ance

noun

In decision-making contexts, the spread of possible outcomes around the expected value; the degree to which results can differ from prediction even when reasoning is sound.

Synonyms: outcome dispersion, result variation, unpredictability

Collocations: high variance, accept variance, variance in outcomes

Example: Even a well-reasoned investment decision will experience variance in outcomes due to market randomness and unforeseen events.

In the articleAccepting variance — the fact that good decisions sometimes produce bad outcomes — is part of becoming a better thinker.

asymmetric payoff

/ˌeɪsɪˈmetrɪk ˈpeɪɒf/|a·sym·met·ric pay·off

noun phrase

A situation in which the potential upside and downside of a decision are unequal in magnitude; where the best and worst outcomes differ significantly in scale.

Synonyms: skewed payoff structure, unequal risk-reward ratio, positive skew

Collocations: asymmetric payoff structure, seek asymmetric payoffs, positive asymmetric payoff

Example: An entrepreneur who can lose $50,000 if a venture fails but can gain $5 million if it succeeds has a positive asymmetric payoff.

In the articleThe most powerful applications involve asymmetric payoffs: cases where the cost of being wrong is low but the benefit of being right is high.

Figurative Phrases

play the odds

To decide based on probabilities; to make choices according to likelihood rather than emotion.

Etymology/Type: Gambling metaphor; "playing the odds" is deciding based on which outcome is statistically more likely.

Synonyms: go with the probabilities, reason from likelihood, bet on what's most likely

Example: Rather than panicking about which topics would appear, she played the odds and focused on the areas most frequently tested.

In the articleThe expected value is (0.5 × 100) + (0.5 × −50) = +25 dollars.

in the long run

Over an extended time period; considering outcomes averaged across many similar decisions.

Etymology/Type: Idiom; over an extended time period, as if life is a run that continues long into the distance.

Synonyms: over time, eventually, across many repetitions

Example: Spending time building strong fundamentals paid off in the long run, even though it felt slow at the start.

In the articleOver many flips, you'll come out ahead by an average of twenty-five dollars per flip.

bet the house

To commit everything or stake all resources on a single outcome.

Etymology/Type: Gambling idiom; to risk everything on a single outcome, as if wagering one's entire house.

Synonyms: go all in, stake everything, put everything on one option

Example: Choosing to study only one possible essay topic and bet the house on it appearing was a strategy that had cost students before.

In the articleAn entrepreneur who borrows everything and bets it on an improbable venture that happens to succeed hasn't made a good decision; they got lucky.

work the math

To calculate deliberately and methodically; to reason through the numbers.

Etymology/Type: Figurative expression; "work" means to calculate deliberately and systematically through the numbers.

Synonyms: run the numbers, do the calculation, reason it through

Example: Before panicking about her average, she worked the math and realised she only needed 68 per cent to still reach her target.

In the articleFor any decision with uncertain outcomes, you multiply each possible outcome's magnitude by its probability, add them up, and compare the options.

stack the deck

To arrange or manipulate a situation unfairly in one's favor.

Etymology/Type: Card game idiom; arranging cards in advance is cheating—figuratively, arranging a situation unfairly.

Synonyms: tilt the odds in your favour, rig the situation, manipulate the conditions

Example: Studying in a distraction-free environment was simply stacking the deck in her favour — and there was nothing wrong with that.

In the articleYou can make an excellent bet and lose. You can make a terrible bet and win.

hedge your bets

To spread risk across multiple options to reduce exposure to loss.

Etymology/Type: Financial/gambling metaphor; a hedge protects against loss—spreading risk protects against complete failure.

Synonyms: spread your risk, cover multiple bases, keep options open

Example: He hedged his bets by preparing thoroughly for three possible essay topics instead of guessing on just one.

In the articleA thoughtful relationship choice that ends painfully wasn't, necessarily, a mistake.

Confusing Words

deliberation vs. deliberate

These share a root but serve different grammatical roles—one is a noun for careful thinking, the other is an adjective or verb describing intentional action.

  • Deliberation means careful consideration before deciding; the act of weighing options — the jury's deliberation lasted three days before they reached a verdict.
  • Deliberate (adj.) means done intentionally rather than by accident; (verb) means to think carefully about something — she made a deliberate choice to pursue the riskier option.

Is the context about the process of careful thinking? Use deliberation (noun). Is it about intentional action or careful consideration? Use deliberate (adj./verb).

probability vs. possibility

These differ in precision and scale—one measures likelihood with a numerical value, the other simply describes whether something can occur.

  • Probability is the measured likelihood of something occurring, expressed as a number between 0 and 1 — the probability of rain tomorrow is 0.7, or 70%.
  • Possibility is the fact that something can happen; whether it is feasible or conceivable — it's a possibility that you might win the lottery, but it's highly unlikely.

Try swapping in a number (0.5, 0.9, etc.). If the sentence still makes sense, use probability. If the context is just 'can this happen?', use possibility.

systematic vs. systemic

These near-homophones differ crucially in meaning—one describes methodical organization, the other describes effects affecting entire systems.

  • Systematic means organized, methodical, and following a regular plan — a systematic approach to studying involved reviewing notes daily and testing herself weekly.
  • Systemic means affecting or permeating an entire system as a whole; embedded in the structure — systemic racism persists because it is woven into institutions and policies.

Ask: Does this describe an organized method or approach? Use systematic. Does this describe something affecting the entire system or deeply embedded in structures? Use systemic.